An endoscope is an elongate tubular instrument that may be rigid or flexible and which incorporates an optical or video system and light source. Typically, the endoscope is configured so that one end can be inserted to some depth into a surgical incision or body cavity via an incision or orifice whereby surfaces on or near the internally inserted end of the endoscope may be viewed by an external observer. A commonly used endoscope is a flexible endoscope called a colonoscope and is used for diagnostic procedures of the human colon. The colon insertion portion of the instrument is approximately two meters long and has one or more hollow channels, or lumens.
Because of the high cost of endoscopes and the need to avoid cross infection from one patient to the next, each endoscope must be thoroughly cleaned and disinfected or sterilised after each use. This procedure is time consuming and presents major difficulties because the endoscope becomes significantly contaminated with biological material from the patient for example mucus, faeces, blood, pieces of tissue and the like.
A typical cleaning procedure involves rinsing and scrubbing the endoscope exterior under running water for some time to remove gross contaminants, subsequently soaking the endoscope in a suitable cleaning bath for 2 to 10 minutes, rinsing the instrument, drying the instrument and then disinfecting it. On some occasions the gross contaminants on the outside of the instrument are inadequately removed by rinsing and the subsequent cleaning bath prior to disinfection. This inadequate external cleaning then compromises the disinfection or sterilisation step since it is impossible to reproducibly disinfect or clean a dirty instrument.
Because the time required for cleaning and disinfection or sterilisation is often longer than the duration of the procedure in which the endoscope is used, capital must be expended on a plurality of instruments or else cleaning becomes the determining factor as to the rate at which procedures can be performed. Moreover a considerable amount of time and materials are consumed in cleaning the brushes and other apparatus used to clean the endoscope including the lumens. Recently attention has been paid to improved methods of cleaning the interior of the lumen (see eg our co-pending application PCT/AU99/00669), however that method is not applicable to the exterior surface. Cleaning the exterior remains a critical, difficult and labour intensive task. Various sophisticated chemical and biochemical products, for example enzyme/detergent compositions, have been developed for use as pre-soaks to loosen contaminants from the exterior surface and to facilitate their subsequent removal by scrubbing. The ultimate efficacy of such treatments is heavily dependant on (a) how diligently rinsing and scrubbing is performed; (b) how much debris is on the surface after the examination and the nature of such debris; and (c) whether the soiled instrument has been allowed to dry prior to cleaning and, if so, the temperature at which this drying took place. Moreover, the present Applicant has found that rinsing and scrubbing with brushes often serves merely to rearrange deposits on the surface of the instrument rather than to remove them. Furthermore, the use of brushes may create a contaminated aerosol which can endanger health-care workers in the vicinity.
Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
It is an object of the present invention to overcome or ameliorate at least one of the deficiencies of the prior art, or to provide a useful or more convenient alternative. It is an object of certain preferred embodiments of the invention to provide a device and methods to improve the speed and/or efficiency of cleaning endoscopes and the like. It is an object of certain highly preferred embodiments of the invention to provide an inexpensive effective device which can be manufactured inexpensively and which can be disposable after a single use.